Power mods for a 250x

[Luke250x]

Hi everyone! I'm new to this set of forums, and I have a few questions. I just sold my 2007 Ktm SXF 250, because it had too much power for the trails I ride. I live in New England, usually riding at 0-1000 feet above sea level, and I typically ride slower trails, but I have plenty of space to open her up. I sold the KTM, because to be honest, it as too. much bike. It was made for the track, and on single tracks, the thing killed me. I picked up a 08 250x instead, with hopes to make it into an r. I absolutely loved the power of the Kim, but the ergonomics of it we're just not there. I looked into getting an r head, and just swapping that in, jetting it, and throwing a Q4 slip on on her, but after looking at more and more peoples opinions, they say that the r head only gives it more top end. I'd like to hear everyone else opinions, because now I'm thinking of jetting it at 155 and 42, cutting up the airbox (already did) and throwing a cam in. Everyone is bullying me now because I bought a pu$$y bike because I can't handle a real one!!! All jokes, but I still want that power back. What's the best way to make easy power on the 250x's that will give me the torque to wheelie in every gear like the r??!! Budget doesn't matter, but don't anyone say buy the KTM back. Also, one additional question; where exactly is the pink wire for the pink wire mod? I've looked all around, and can't find it. Most said behind the left rear number pane, but I didn't see it. Anyways, any help is appreciated, and feel free to ask me anything about the bike, I can answer most questions if that helps you figure out what I should do. And one last thing, the stock seat is wayyyy to firm and skinny. Where can I get a soft wide gel seat like the old guys throw on their Suzukis! 

[Jim Dettman]

<<Everyone is bullying me now because I bought a pu$$y bike because I can't handle a real one!!!>>

 I'm not being disrespectful here, but the saying that ridding well is 80% rider and 20% bike is generally true.   Technique can make up for a lot. I've seen a good 125cc rider leave a 250cc rider in the dust.   For woods ridding, a 250 is generally adequate for most, unless you happen to be tackling some steep mountains.

<<What's the best way to make easy power on the 250x's that will give me the torque to wheelie in every gear like the r??!! Budget doesn't matter>>

  2008 R head, stage 1 Hot Cam, Un-restricted exhaust, rejet, and 13/51 gearing.

<<but don't anyone say buy the KTM back.>>

 With that said, it's a bit like putting lipstick on a pig.   The 250x is heavy compared to most bikes.  Doing the above will get you towards your goal, but at the end of the day, it's still a 250x.   Another option BTW is to go with a big bore kit and get closer to 300cc's.

 However I would strongly encourage you to find a 250x that has been somewhat modified and beg for a ride on it because you could spend a lot of money on it and still end up disappointed.  A wiser choice may be to simply buy another bike.

 But a couple things:

1. Make sure it is jetted correctly.  The bikes come way lean from the factory.  Do open up the air box, even with the stock exhaust.

2. Pickup a 13t countershaft sprocket.  For $15 or so bucks, it's a quick way to find out if you can get the kind of torque you are looking for.

 after that, move onto the exhaust.  A rejet will be required.   If that doesn't get you there, then move onto the cam and the head.  

<< Also, one additional question; where exactly is the pink wire for the pink wire mod?>>

  You don't need it.   A X motor is basically a re-tuned R motor giving you more low end power.   The pink wire mod adds 500k to the rev limiter and alters the advance curve.  It's designed to be used with the R setup, which is a different header pipe, cam, and head, and designed to give you power in the mid to upper RPM's, none of which you want in a woods bike.  Most can't tell the difference with it connected or not with the stock setup.

FWIW,

Jim.

 

 

 

[Luke250x]

Thanks for all the info! I ordered jets, and I think I'll order a slip on and a 13t front sprocket, and maybe go at the airbox some more, but I don't think so. I took the snorkel off, and drilled some big holes on the top. I did a bunch of research before I bought the bike, and I did find that they run extremely lean from the factory. I think that just for now, I'll run a 2008 R cam, jets, 13t front sprocket, air box mod, and maybe a slip on, depending on how much I can get one for. I was reading old threads, and people say that the Dr. D exhaust is the best, but the threads were old and I couldn't find any for sale now. I don't want to buy a bad amazon 30$ pipe, but I also don't want to be spending 400$ on a slip on just to let her breathe. I know, I could just chop the stock one up a bit, but I really do like the sound that a slip on makes. A buddy has one on his stock 250x, and it does sound deeper. 

[Jim Dettman]

Don't bother with an R cam....it's for power in the mid to upper rpm range and requires a different head pipe.  A stage 1 Hot Cams would be best.

As for the exhaust, many like the Lexx slip-on.  Not super expensive and it does a decent job.

Jim.

Edited April 28, 2021 by Jim Dettman

[Luke250x]

Ok, I'll go ahead and grab a sage one hot cam for now, and maybe in the future get a 250r header and cam. Thanks for the help! If anyone else sees this thread, feel free to add your suggestions, I'm open for any tips!

[RichIOM]

Your post is quite contradictory because it started out stating the KTM was too powerful for the type of riding you do, but then quickly followed with how do you get that power back on the X.

It reads like you’re more bothered about what people think than what is right for you.

Theres no such thing as a “pu$$y bike”, just individual ego and peer pressure.

You do you, ride safe and enjoy it, that is literally all that matters.

Good luck and enjoy. 

[Luke250x]

31 minutes ago, RichIOM said:

Your post is quite contradictory because it started out stating the KTM was too powerful for the type of riding you do, but then quickly followed with how do you get that power back on the X.

It reads like you’re more bothered about what people think than what is right for you.

Theres no such thing as a “pu$$y bike”, just individual ego and peer pressure.

You do you, ride safe and enjoy it, that is literally all that matters.

Good luck and enjoy. 

yeah, I see that now.... should've read the post over before I posted it. What I mean is that for the power the Ktm had, and the size it was, it was just too much bike, so I'm trying to get similar power out of my 250x motor, but since it is a smaller bike overall, I can handle it better. And yes, I know I shouldn't, but I let the voices of everyone else get into my head. I personally think that the bike is very underpowered for a 250, so everything together just makes me want to give her more power. I also have ridden one with a r head and cam, and it was a huge difference (obviously). For now, I think I'll just get a hot cam for it and throw on a slip on fmf my buddy had laying around, jet it, and see how she goes. now, If I were to keep the stock exhaust and put an R header pipe on, and throw in a stage 2 cam instead of stage 1, what would the power difference be, if it's possible? I don't plan on changing valves or even taking the head off, just dropping a hot cam in and send her! What does everyone think? I know I'm asking a lot of questions, just new to the 250x and I appreciate any advice?

Edited April 28, 2021 by Luke250x

[RichIOM]

Definitely steer clear of what others think, it’s what you think that matters, too many waste time sweating stuff that doesn’t matter.

Yes the X isn’t the most powerful bike in the world but it’s a solid bike that’s well planted.

What head and cams you go for really depends on your riding.  If it’s more technical you don’t want an R head and you’ll want a stage 1, but as above add things incrementally so you can determine whether there’s any need for more $ on it.

Open up the airbox if not already and get the jetting right with JD kit.

After that I’d get the hearing sorted, 13 front, 51 rear would be a good choice.

Next I’d go for a stage 1 for riding that isn’t all top speed, over a slip on, and then get a slip on and rejet further if more is still needed

After all that if you still want more and happy to pump more $, over trading for a different bike, then look for a big bore kit.

If it was me and I was getting to the big bore consideration, I’d be looking for either a 250RX or 450RX at the point if you want to keep riding red ?

[Luke250x]

9 minutes ago, RichIOM said:

Definitely steer clear of what others think, it’s what you think that matters, too many waste time sweating stuff that doesn’t matter.

Yes the X isn’t the most powerful bike in the world but it’s a solid bike that’s well planted.

What head and cams you go for really depends on your riding.  If it’s more technical you don’t want an R head and you’ll want a stage 1, but as above add things incrementally so you can determine whether there’s any need for more $ on it.

Open up the airbox if not already and get the jetting right with JD kit.

After that I’d get the hearing sorted, 13 front, 51 rear would be a good choice.

Next I’d go for a stage 1 for riding that isn’t all top speed, over a slip on, and then get a slip on and rejet further if more is still needed

After all that if you still want more and happy to pump more $, over trading for a different bike, then look for a big bore kit.

If it was me and I was getting to the big bore consideration, I’d be looking for either a 250RX or 450RX at the point if you want to keep riding red ?

That sounds like a solid plan. Especially the riding red part! I bought a ton of jets on amazon in a pack, so I'll be set with those. I'm pretty good with carbs and jetting, done it plenty of times before, so I think I'll be able to figure that out just fine. Airbox is opened up, and I'll order a stage 1 cam asap. I appreciate all of the insight, and hope everyone can get out and ride soon!

[TDW]

Dont know if you have seen this site but there is alot of good information about the 250X, including the CCC mods that help to wake this bike up some. 

https://www.rickramsey.net/CRF250X.htm

Mostly talking about the older 250X bikes but still worth browsing.

[mlatour]

 

Keep in mind that even with 'power mods' added to the CRF250X engine,

unlike a motocross race bike it has a wide-ratio gearbox so there is a bigger rpm drop each time you shift,

meaning it won't be a 'wheelie in all gears' machine if that's what you're after.

 

Durelle Racing makes a soft gel seat, it's also slightly wider than stock.

 

Edited April 29, 2021 by mlatour

[Chuck.]

+1 on the Rick Ramsey web site.

The 2 most important considerations is the type of terrain you ride and your expectations and skill level. Not bragging but I've ridden a lot of different terrain and competed in a variety of events from Scrambles, MX, Desert Cross County, and many Enduros.  I also trail ride the wet PNW and Cascade Mountains. And my preference for bikes has changed over the years; I use to ride open class 2Ts and 4Ts, but the modern 250s provide similar power and less weight. My ideal bike for a novice is an 86+ XR200R because the power won't kill you and you will learn technique.   The secret to getting from point A to point B along 70-100 miles of trails in the woods among a bunch of other competitors is to always keep moving, avoid all stops, and don't get tired. I jogged a mile a day and rode a XR200R and for years had single digit seasonal scores.

My current favorite trail bike is a much modded 01 XR200R with a Powroll 218 engine and upgraded suspension, the only thing stock is the frame and plastic.  The engine has more torque than a XR250R and the bike is 30 lbs lighter than a XR250R, and better suspension.  One of my best mountain bikes was a Suzuki RM with a XR engine because the MX chassis just worked the best and the XR200 engine had the best power delivery for the terrain.  A stock XR200R in a drag race will be beat by almost any bike, its secret to success on the trails is the nice tractable power delivery; when the going get tough the little R just delivers.

I also have a CRF250X with most of the CCC mods and JD Jetting, plus a flywheel and it is a very good trail bike but the long MX chassis doesn't have the agility of my XR.  It also required extensive suspension revalving for PNW trails.  I experimented with a R header and strait thru Yosh mufflers but went back to stock X exhaust because it seemed better for my terrain. It now has near XR250R low end power and its 30hp is a lot of fun on open trails.

So don't dis the 250X as I consider it a next gen XR250R. Have said that it may not be the best choice for your terrain but with info on this forum you can get it to be a very good trail bike.  I went for a ride last summer with some riders from CA, one on a 450 and the other on a 300 2T.  The 450 rider suffered badly on the wet tree roots and clay. The 300 2T did good.  So rider or bike, I don't know.

The X can be tuned to behave in a variety of different ways and the FCR carb is near EFI.  I have a friend with an EFI bike and I really like the throttle response but he says it is difficult to ride when he is tired, so be careful what you wish for. However the X does seem to need some tuning for best results, info on this forum. For tight trails the extra flywheel weight was a big improvement.  I've considered using the 07 R head but the gain is so low it doesn't get done.  I'm also a AZ Snowbird and  I'm taking my X back to AZ and leaving my XR218 in the PNW (very different terrains).  I kept stock gearing on my X because it is plated and I do ride some roads to connect trails, but if trail only dropping one tooth on the counter shaft is noticeable. With stock gearing I do need to use the clutch a lot on tight technical but the clutch seems to hold up better than my XR on the same trails.

My suggestion is to ignore your local pundits and ride the bike. Do some mods listed on this forum and evaluate them on your terrain to decide if they are worth keeping. I connected the pink wire to a handle bar switch and couldn't detect a difference during trail riding so it now stays connected. I've tried disconnecting the TPS plug and that does make a difference on part throttle throttle response, which is good during low traction conditions, I may hook that up to a handle bar switch for easier switching. 

Lots of good info in the previous posts.

Edited April 29, 2021 by Chuck.

[twigster]

I have done most things to my 04 crf 250 x it keeps up with 09 250 r (my friends) and i dont need any more power .. It has a 280 big bore ( which can take time to spool up) an R cam ,ported head ,vortex ignition FmF power bomb exhaust and lots more ,I feel the the real benefit for me is that i never bought anything new for my bike i bought everything used etc i know your not worried about the money but i dont have bundles invested in this and i was offer'd 4k for for it ...These bikes dont go wrong and if looked after they are appreciated by a larger group of people so re-sale can be good )

The best money i spent to improve my bike was a lithium battery saved lbs , i got a great set of sticky tyres ,got the suspension where it worked for me ,jetting is a must, air box mod was a must a pipe helped!!!!!!!!

..People here said the R cam will give more mid , top end i would go further and say it may even sacrifice a little low end ,..Now that i have nearly finished my build i can say from mx ,enduro ,cross country even some extreme enduro not much)this bike cant do its the swiss army knife of bikes so if your friends think your bike cant cut it take them somewhere else your x will still work whilst they may  struggle ....P.s Honda kits are available for the newer R and Rx to make a really competative 300 ,whilst you have not invested a great deal at this momentyou can  sell it and go that route ..good luck whatever you choose the X wont let you down... David knight also raced a 250 x so the bike is capable